Post-hole digger.



1 PATBNTED JULY 14, 1908. E. M. KRAMER a; J. w. KAUFMANN.

" POST HOLE-BIGGER.

APPLIOATION mum nov. 1, 1907.

' 2 sums-sum? 1.

E. M. KRA1MBRI&.J. w-. K'A'UPMA'NN. Pos r HOLE BIGGER.

APPLICATION rush NOV. 1, 1907.

PATENTED JULY 14, 1908.

2 sums-51mm 2.

UNITED'STATES PATENT OFFICE.

EMIL M. KRAMER AND JOHN W. KAUFMANN, OF PAXTON, ILLINOIS.

I POST-HOLE DIGG-ER.

Specification of Letters Patent.

Patented July 14, 1908.

To all whom it may concern:

Be it known that we, EMIL M. KRAMER and JOHN W. KAUFMANN, citizens of the United States, residing at Paxton, in the county of Ford and State of Illinois, have invented a new and useful Post-Hole Digger, of which the following is a specification.

This invention relates to post hole diggers and its object is to provide a simple and efficient deviceof this character which can be readily adjusted so as to dig holes of different diameters.

Another object is to provide means whereby the operator is enabled to remain in substantially the same posture at all times during the digging operation.

Another object is to provide simple and eflicient means whereby the necessary adjustment of the parts can be readily effected.

With these and other objects in view the invention consists of certain novel features of construction and combinations of parts which will be hereinafter more fully described and pointed out in the claims.

In the accompanying drawings is shown the preferred form of the invention.

In said drawings: Figure 1 is a view partly in elevation and partly in section of a digger embodying the present improvements. Fig. 2 is a perspective view of a portion of a modified form of stem. Fig. 3 is a longitudinal section through a portion thereof. Fig. 4 is an elevation showing a modified form of securing means designed to be used in connection with either form of stem. Fig. 5 is a detail view of another form of securing means. Fig. 6 is a view similar to Fig. 1 and showing the tool provided with a modified form of head. Fig. 7 is a horizontal section through said modified form of head. Fig. 8 is a detail view of the bit used in connection with the head shown in Figs. 6 and 7.

Referring to the figures by characters of reference, 1 designates a yoke made up of similar 0 positely disposed lapping bars 2 each of which is curved in the direction of its length and provided with a series of openings 3. The openings in the two bars are designed to register and one opening of each series is disposed to receive a bolt 4 or other fastening means insertible transversely through a yoke 5 which is formed at one end of a stem 6. As shown in Fig. 1 this stem, which may be of any suitable length, has a spiral groove therein and formed within the inner wall of each whirl of the groove is a re- -this lever with bell crank lever 12. ferred, a suitable spring such as indicated at 17 may be employed so as to hold the plunger cess 8, all of the recesses being preferably disposed in alinement. A tube 9 is telescopically mounted upon stem 6 and carries a handle 10 at its free end while arranged upon the tube adjacent its other end is a bracket 11 in which a bell crank 12 is pivotally mounted. A plunger 13 is pivotally connected to this bell crank lever and is designed to project into an opening 14 in sleeve 9 and to engage any one of the notches 8. A small operating lever 15 is pivotally connected to the sleeve close to the handle 10 and a rod 16 connects If pre- 13 normally pressed into the groove 7.

The lower or free ends of the bars 2 are fastened to a head consisting of oppositely disposed blades 18 disposed in the usual manner and preferably formed in a single iece of sheet steel and connected at their ower ends by a web 19. Each blade is preferably reduced in thickness at the bend therein as indicated at 20 so that the same can be flexed to spread the head laterally when the bars 2 are adjusted relatively to each other.

In using the herein described device the lever 15 is drawn toward handle 10 and the plunger 13 therefore withdrawn from the notch 8 engaged thereby. The sleeve can then be turned upon the stem 6 until the lunger 13 assumes a position within the owest notch 8. The digger is then used in the ordinary manner the blades, by being forced downward and rotated, collecting the dirt therebetween. As the digger is forced into the ground the plunger 13 can be withdrawnfrom the notch in which it is seated and the sleeve rotated until the lunger registers with another notch. It Wlll thus be seen that the distance between the handle and the blades 18 can be increased in proportion to the depth of the post hole so that the operator can remain practically in the same posture at all stages during the digging operation.

Instead of providing a bell crank lever with a lunger pivotally connected to it as heretofbre described said bell crank lever may have an integral arm 21 as indicated in Fig. 5 said arm being disposed to pass through the sleeve and into engagement with the stem. Also, if preferred, a lever such as shown in Fig. 4 may be employed. This lever is centrally fulcrumed upon a bracket as indicated at 22 and has a locking arm 23 extending from one end while a spring 24 bears against its other end and serves to hold the arm normally in engagement with the stem in the sleeve. The operating rod 25 may be connected to an ear 26 extending from the lever.

Instead of providing the stem with a spiral groove, the adjustment of the handle in relation to the blades may be more quickly effected simply by providing the stem with a longitudinal groove 27 as indicated in Fig. 2. This groove has a series of notches 28 therein designed to be successively engaged by the plunger 13 or the locking arm of the bell crank lever, according to the form of locking device employed, and the upper wall of each notch is preferably beveled as indicated at 29 so that simply by pulling upward on the handle the plunger can slip out of a notch and move into position to engage another notch.

It will of course be understood that the distance between the two blades 18 can be readily changed by removing the bolt 14 and adjusting the bars 2 toward or from each other within yoke 5. As the two blades are flexible at the bends 20 it will of course be obvious that they will bend at these joints to permit any adjustment which takes place between the bars 2 and at the same time spread the head laterally.

As indicated in Fig. 1 the blades 18 are provided with converging points or tongues 30 designed to bite into the ground when the tool is rotated. In lieu of this construction, however, the digging head of the tool may be formed as shown in Figs. 6, 7 and 8. It will be seen that in this construction the head is formed of two oppositely disposed bowed blades 31 having longitudinal slots 32 in their lower ends which lap and receive a threaded stem 33 bit 34. It is designed to screw a nut upon the stem so as to clamp the slotted ends of the blades 31 together. Each blade has an offset portion 35 adjacent its slot which extends downward and is pointed as at 36 so as to constitute a bit.

What is claimed is:

1. The combination with telescopically connected members and means for locking said members in adjusted position; of a handle upon one of the members, oppositely disposed blades, and arcuate lapping bars eX- tending from the blades and adjustably connected to the other member.

2. The combination with telescopically connected members, one of said members having a groove provided with a plurality of notches; of a handle upon one of the members, a blade connected to the other member, and means upon one of the members and slidable within the groove for engaging one provided with a tapered of the notches to lock the members in adjusted position.

3. In a device of the character described the combination with telescopically connected members, one of said members having a groove formed with notches; of a handle upon one of said members, a spring pressed locking device upon said member and movable within the groove of the other member and disposed to be automatically seated, within any one of the notches, and a blade connected to the grooved member.

4. The combination with telescopically connected members, one of said members having a groove provided with a plurality of notches; of a handle upon the other member, means carried by said member and movable within the groove for engaging one ol the notches to lock the members together, oppositely disposed digging blades and adjustable connections between said blades and the grooved member.

5. In a tool of the character described a digging head comprising oppositely disposed bowed. blades having slotted lapping ends, means within the slots 'for binding said ends together, and laterally displaced downwardly inclined bits upon the blades and adjacent the lapping ends thereof.

6. In a tool of the character described a digging head comprising op msitely disposed blades having lapping ends, laterally displaced downwardly inclined bits integral with the blades and adjacent their lapping ends, and means extending through the lapping ends for binding them together, said means having an end portion constituting a bit.

7. In a tool of the character described a digging head comprising oppositely disposed blades adjustably connected at one end and non-pivotally connected at their other end, said blades being movable relative to each other to spreadv or to contract the head.

8. In a tool of the character described the combination with a stem and a handle adjustably connected thereto; o'l a digging head comprising oppositely disposed blades nonpivotally connected at their lower ends, oppositely disposed depending bits integral with the head and adjacent the connected ends of the blades, and adjustable connecttions between the blades and the stem, said blades being relatively movable to spread or to contract the head.

In testimony that we claim the foregoing as our own, we have hereto affixed our signatures in the presence of two witnesses.

EMIL M. KRAMER. JOHN W. KAUFMANN Witnesses:

J. B. SHAW, WM. H. WHITE. 

